Fun (was Re: Cubist's first bug report)

[dsc at swcp.com]

Just for fun:

on mouseUp
   put LF into newLine
   put 0 into sRandomCount
   put "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16" into myVar
   repeat 100
      add zero to any item of myVar
      put myVar & newLine after myTempList
   end repeat
   put  sum(myVar) & newLine & myTempList
end mouseUp



> On Jun 5, 2016, at 1:15 PM, dsc at swcp.com wrote:
> 
> Here's a script (derived from Mark's) that illustrates the double call:
> 
> local sRandomCount
> 
> on mouseUp
> 	put LF into newLine
> 	put 0 into sRandomCount
> 	put "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0" into myVar
> 	repeat 100
> 		add 1 to item myrandom(16) of myVar
> 		put myVar & newLine after myTempList
> 	end repeat
> 	put sRandomCount & tab & sum(myVar) & newLine & myTempList
> end mouseUp
> 
> function myRandom n
> 	add 1 to sRandomCount
> 	return random(n)
> end myRandom
> 
> 
> 
> 
>> On Jun 5, 2016, at 12:42 PM, Dar Scott <dsc at swcp.com> wrote:
>> 
>> Very nice and clean example code.  
>> 
>> Also, as you hinted, this does have the problem:
>> 	add 1 to item random(16) of myVar
>> 
>> I infer from this that the problem is very likely not in how 'any' counts items.  
>> 
>> This also applies to subtract and multiply.  I suspect that random(16) is being evaluated twice based on a first glance at the pattern.  Because of that, my guess is that this bug will not cause a crash.  
>> 
>> The problem also occurs when I use my own random function.  
>> 
>> it looks as though this...
>> 	add 1 to any item of x
>> ... is being evaluated as...
>> 	put 1 + any item of x into any item of x
>> ... which is incorrect.
>> 
>> Perhaps that is just the info needed for a quick fix.  
>> 
>> This also will show up for any function with side effects built-in or not, so this is a far ranging bug and it should be pushed up in priority.  
>> 
>> Dar
>> 
>> 
>>> On Jun 5, 2016, at 8:48 AM, Mark Schonewille <m.schonewille at economy-x-talk.com> wrote:
>>> 
>>> Hi Quentin,
>>> 
>>> I see the same results, when I try your code. However, if I first store the random value and add 1 to an item in the string in the next line in the script, it works correctly. Apparently, the random function and the add command are incompatible.
>>> 
>>> on mouseUp
>>> put "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0" into myVar
>>> repeat 100
>>>    put random(16) into myRandom
>>>    add 1 to item myRandom of myVar
>>>    put myVar & cr after myTempList
>>> end repeat
>>> put sum(myVar) & cr & myTempList
>>> end mouseUp
>>> 
>>> Kind regards,
>>> 
>>> Mark Schonewille
>>> http://economy-x-talk.com
>>> https://www.facebook.com/marksch
>>> 
>>> Buy the most extensive book on the
>>> LiveCode language:
>>> http://livecodebeginner.economy-x-talk.com
>>> 
>>> Op 05-Jun-16 om 16:12 schreef Quentin Long:
>>>> Code which exhibits the bug:
>>>> 
>>>> on mouseUp
>>>> put "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0" into Fred
>>>> repeat 100 times
>>>>    add 1 to any item of Fred
>>>>    put Fred into line (1 + the number of lines in fld "testbed") of fld "testbed"
>>>> end repeat
>>>> put sum (Fred) into line (1 + the number of lines in fld "testbed") of fld "testbed"
>>>> end mouseUp
>>>> 
>>>> This handler *should* end up generating a 16-item string of integers which sum to exactly 100. What it *actually does* end up generating, is a 16-item string of integers whose sum may or may not fall somewhere within the range 80-120. Not sure what the hell is going on here, but I am not at all happy about it. Perhaps other people might like to try this code on their systems, and see if it works as intended for them?
>>>> 
>>>> http://quality.livecode.com/show_bug.cgi?id=17795
>>>> 
>>> 
>>> 
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>> 
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